Currently, in a communications system, most spectrum resources in a low frequency band (for example, a frequency band not higher than 3 GHz) that are applicable to a mobile communication device have already been allocated completely; however, a large quantity of spectrum resources in a high frequency band (for example, a frequency band: 3-300 GHz) have not been allocated for use. According to a definition by the International Telecommunication Union (International Telecommunication Union, ITU), the high frequency band is also referred to as a millimeter wave band. Currently, there are some solutions that use a millimeter wave band to perform cellular communication, and details are as follows:
Generally, a cellular base station and a millimeter wave base station are deployed on a network side, the cellular base station communicates with user equipment by using a cellular band, and the millimeter wave base station communicates with the user equipment by using a millimeter wave band. Therefore, two transceivers need to be deployed in the user equipment, where one transceiver is configured to communicate with the cellular base station, and the other transceiver is configured to communicate with the millimeter wave base station. In addition, because a frequency of the millimeter wave band is extremely high, a power requirement on and complexity of a transceiver configured to communicate by using the millimeter wave band are relatively high, which increases a cost of the user equipment.